The aim of our studies is to evaluate the effects that radionuclides in the environment (from power production) will have upon a local population and upon the global population, The critical nuclides for nuclear power are the alpha emitters Pu239, Pu238, Am24l, Cm242 and Cm244, and the beta emitting fission product krypton-85. Our studies will provide internal dose estimates for exposure to these emitters via air food pathways. The dose estimates are derived for particular cells, since it is known that certain types of tumors are most significant. For the alpha emitters the dose estimates will be to basal cells in bronchial epithelium in the upper bronchial airways and to osteoprogenitor cells on bone surfaces. For the beta emitter krypton-85, which is soluble in fat within bone marrow, the critical cells are hemopoietic cells as well as osteoprogenitor cells on bone surfaces. We intend to compare the various internal doses associated with nuclear power production with those delivered by the release of naturally occurring alpha emitters from conventional coal or oil fired power plants. In this way it will be possible to give a valid comparison of the radiation risk associated with nuclear power generation.